For daytime privacy, you should consider a medium or dark tint which makes the glass at least twice as reflective from the outside. You should only need to shut your curtains or blinds at night. In places where there is not much light reflecting off the window you would need a darker tint to give the same amount of privacy.
Another option for privacy on some windows is a frosted film which gives almost complete privacy, day or night. The frosted films let most of the light pass through, but you can only see things through the film that are up against the other side of the glass. The film can be applied in bands or patterns to give privacy in certain areas and a clear view through the rest of the glass.
These films can also be computer cut or printed on using a large format printer for graphics and signage.
The frosted films come is several variations, from bumpy clear films to smooth white and some have fine sparkles in them which really sparkle in the sun or bright lights.
Frosted films are popular on the front entrance of a house and internal glazing in office buildings.